Jeff Chiu, Associated Press
A rainbow flag hangs from the office of the San Francisco Mayor in 2013.
A lot of people think it's a given that the Supreme Court would accept it. I wonder. I think the Supreme Court might want to wait for a few more circuits to decide the issue. —Michelle Mumford, assistant dean of admissions, BYU law school

SALT LAKE CITY — Possible outcomes in Utah's appeal of the court ruling that overturned its ban on same-sex marriage range from clear to complicated.

And whatever a three-judge panel in the 10th Circuit Court of Appeals decides will likely be challenged with further litigation.

"There's actually a whole menu of things that could happen," said Troy Booher, a Salt Lake appellate attorney.

The judges have pored over thousands of pages of briefs from attorneys for the state and the three gay and lesbian couples who challenged the Utah ban, as well from at least 50 parties on both sides. They also heard arguments in an hourlong hearing last month.

A decision could come in weeks if not months, though the court seems poised to act sooner rather than later due to cases pending in other federal appellate courts. The 10th Circuit ruling could have huge implications in other cases.

The three-judge panel does not have to be unanimous, and there could be agreement on the result but not on the reasoning in a split decision.

The judges' first two options seem fairly obvious.

The panel could find the state's voter-approved Amendment 3 that defines marriage as between a man and woman constitutional and reverse U.S. District Judge Robert Shelby's decision that struck down the law.

The judges could affirm Shelby's decision on any grounds, which would make same-sex marriage legal in Utah and the five other states — Colorado, Kansas, New Mexico, Oklahoma and Wyoming — in the 10th Circuit's jurisdiction.

It's unclear whether that would immediately trigger a rush to county clerks offices for marriage licenses as Shelby's ruling did in December. The U.S. Supreme Court put gay marriages on hold in Utah "pending final disposition" of the appeal in the 10th Circuit.

"What that means is not well defined, frankly," Booher said. "I think how to interpret that Supreme Court order is much more important than trying to figure out the inner workings of stays of decisions."

It could leave county clerks in a pickle, he said.

"If you're the county clerk, I think you're going err on the side of caution," Booher said.

According to the Utah Attorney General's Office, a one-week stay is automatic in appeals court cases because the court waits that long to issue its mandate or order on the decision.

Shelby denied the state's request for a stay of his ruling and the 10th Circuit twice rejected the state's petitions. More than 1,200 same-sex couples married over a 21-day period before the Supreme Court stepped in.

"We'll be ready for all contingencies," said Missy Larsen, spokeswoman for the Utah Attorney General's Office.

With either outcome, the losing side could seek what is called en banc review. That would put the case before all 11 judges, including the three originally assigned judges, in the 10th Circuit.

"In other words, the whole thing starts over," said University of Utah law professor Cliff Rosky.

Those judges, including two from Utah — Scott Matheson Jr. and the recently appointed Carolyn McHugh — would ask the parties to file new briefs and hold another round of oral arguments, pushing a final decision out for months.

Having the entire bench weigh in on the case could give rise to multiple and divergent opinions. Also, the judges in their deliberations would not be bound by previous 10th Circuit decisions but would be subject to U.S. Supreme Court rulings, Rosky said.

But the appellate court rarely grants en banc review.

Another possibility after the three-judge panel's decision is for the losing side to petition the Supreme Court, which only hears a small percentage of cases it's asked to take it up.

"A lot of people think it's a given that the Supreme Court would accept it. I wonder. I think the Supreme Court might want to wait for a few more circuits to decide the issue," said Michelle Mumford, assistant dean of admissions at the BYU law school and a former 10th Circuit Court clerk.

Cases are pending in four other federal appellate courts. After those possible outcomes, "we get into the weird," Rosky said.

"There are some complicated possibilities if the court makes a decision based on jurisdictional grounds, he said.

In oral arguments last month, the judges asked about legal standing in both the Utah and Oklahoma cases, though it seemed to be more of an issue in the latter. Attorneys in the Utah case did not address jurisdictional issues in their briefs. Standing has to do with whether the party has the right to assert its claim.

Two of the three couples in the Utah case are not married, while the other couple married in Iowa. The plaintiffs are suing for both the right to marry and to have marriages performed in other states recognized in Utah. They named the governor, the attorney general and the Salt Lake County clerk, who oversees the issuing of marriage licenses, as defendants.

But only the governor and the attorney general appealed Shelby's ruling.

Rosky said its possible the court could find the state doesn't have standing on the licensing issue but does have standing on the recognition question.

After the hearing, the state argued in a two-page brief that it does have standing because Shelby found the state's marriage law unconstitutional and stopped the governor and attorney general from enforcing it.

Mumford said appellate judges like to bump cases down to the district court on jurisdictional grounds because it's safer and easier.

The 10th Circuit could also kick the case back to Shelby if it sees the need for a trial on the evidence, which in Utah could center on same-sex parenting versus heterosexual parenting. But most court observers say that is unlikely.

The Utah case is the first to reach a federal appellate court since the U.S. Supreme Court struck down part of the Defense of Marriage Act in U.S. v. Windsor last summer.

A year ago last month, Derek Kitchen and Moudi Sbeity, Laurie Wood and Kody Partridge, and Karen Archer and Kate Call challenged Utah's law against same-sex marriage in federal court. Archer and Call were married in Iowa and sued Utah to have their union recognized as valid.

Since the high court ruling on DOMA, 11 federal judges, including Shelby, have struck down state bans on gay marriage or on the recognition of same-sex marriage from other states.

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